The cyclone dust separator is a type of latest vacuum cleaner, which is free of a conventional dust collecting bag and filter system, but causes the air flow to flow through one or more cylinders along a high-speed spiral path. When the air flow makes the rapid movement along the spiral path, dust and particles will be thrown out of the air flow due to the strong centrifugal force. In this way, there is no need to use any kind of filter for separating dust from the air flow, with dust being collected at the bottom of the cylinder.
Relative to the conventional vacuum cleaner, the cyclone dust separator has the notable advantages. There is no need to replace the dust collecting bag, and the suction force will not weaken with increase of the garbage. Thus, the cyclone dust separator has been widely used at present.
To further enhance the dust removal effect, the cyclone dust separator normally comprises a multistage cyclone dust separator. Currently, the two-stage cyclone dust separator is popular thanks to its simple and compact structure and low cost.
The Chinese patent CN203468515U discloses a typical two-stage cyclone dust separator. In this two-stage cyclone dust separator, the outer air inlet is tangential to the housing of the first stage dust separation unit, and the inner cyclonic conical drum acting as the second stage dust separation unit is arranged coaxially with the housing of the first stage dust separation unit. Most of the dust can be separated from the air and falls onto the bottom of the first stage dust separation unit. Only a small part of the unseparated dust enters the inner cyclonic conical drum, and then is separated by the inner cyclonic conical drum and falls onto its bottom.
Such typical two-stage cyclone dust separator is designed as floor type, and is normally placed on the horizontal floor, wherein the axis of the inner cyclonic conical drum is in a vertical state, and the user just needs to control the suction port at the end of the extension tube, so as to better carry out the dust removal operations. Therefor, the dust suction devices having the similar two-stage cyclone separator all are configured to be vertically disposed for operation.
However, if the angle of the cyclonic conical drum of the two-stage cyclone dust separator is frequently changed or adjusted, even in the horizontal direction, at least two problems will be encountered: firstly, all the dust rotates always in the first stage dust separation unit, and secondly, only a limited part of the dust may accumulate on the bottom of the dust suction device.
The above problems will result in that a great deal of dust is suctioned into the inner cyclonic conical drum or air outlet unit, thereby blocking the filter at the outlet in short time. Here, the separating efficiency and performance of the dust suction device will be lowered to a very low level. Thus, it is difficult to operate the conventional two-stage cyclone dust separator in the horizontal orientation, limiting the operation by the user.
Thus, it is urgent to make an improvement to such a two-stage cyclone dust separator, so as to enable it to be operated both in the vertical orientation and in a certain angle range offset from the vertical orientation, even in the horizontal orientation.